log4net 无法输出日志，跟踪发现IsErrorEnabled等，都是Flase。

private static readonly ILog Log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);

protected void Page_Load(object sender, EventArgs e)
        {
            try
            {
                Log.Error("输出日志");
            }
            catch(Exception ex)
            {
                Log.Error("输出异常日志");
            }
        }

<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net"/>

<log4net>
        <appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender">
            <file value="log\\"/>
            <appendToFile value="true"/>
            <rollingStyle value="Composite"/>
            <maxSizeRollBackups value="-1"/>
            <maximumFileSize value="10MB"/>
            <staticLogFileName value="false"/>
            <DatePattern value="yyyy-MM-dd&quot;.txt&quot;"/>
            <layout type="log4net.Layout.PatternLayout">
                <conversionPattern value="%date [%thread] %-5level %logger [%property{NDC}] - %message%newline"/>
            </layout>
        </appender>
        <root>
            <level value="DEBUG"/>
            <!--1. ALL 2. DEBUG  3. INFO 4. WARN 5. ERROR 6. FATAL 7. OFF-->
            <appender-ref ref="RollingFileAppender"/>
        </root>
    </log4net>

var path = AppDomain.CurrentDomain.BaseDirectory + @"\log4net_config.xml";
   log4net.Config.XmlConfigurator.Configure(new FileInfo(path));